Innovation for Athletes256 MB built-in memory 100% skip-free Audio Wireless Speed and Distance monitor On demand Audio Feedback onspeed, distance and time. Auto-tracking of all run data Digital FM tuner with 10 presets Wearable Sport armband Strobe light to be be more visible in low-light conditions MP3 and WMA playback Backlit LCD displayBuilt-in rechargeable battery 10 hours battery life Easy menu navigation Shuffle and Repeat modes Equalizer for optimized sound to suit your music style Dynamic Bass Boost electronically enhances the low tones Digital Media Manager for easy media management Works with PC and Mac Don't give up your radio: Enjoy your favorite radio programming with the built-in FM tuner and 10 station presets.Sport features: Wireless speed anddistance sensor tracks your workout progress. You can store the data on the player and upload to your online training log later. Audible feedback gives you time, distance and pace on demand. Strobe light adds visibility.